Foam seats commonly consist of a synthetic foam cushion having an upper surface having a vinyl flexible cover bonded thereto and the cushion is supported on its bottom and rear surfaces by a relatively rigid pan of sufficient strength to support the seat user's weight. Various arrangements have been used to attach the cushion to the pan and various retainers and decorative trim and crimp edge attachments are used with the pan to encase the pan peripheral edge and otherwise provide an attractive and practical transitional junction between the covered seat cushion periphery and the pan periphery.
The cushion cover may be tucked under seat components such as shown in U.S. Pat. No. 3,851,920, or may be tensioned to attach the pan to the cover such as shown in U.S. Pat. No. 3,778,104.
It is also known to tuck the peripheral region of the foam seat cover intermediate the bottom surface of the seat and the pan as shown in U.S. Pat. Nos. 3,222,698 and 4,566,735, but such constructions require relatively complicated assembly techniques not readily produceable under high production conditions.
In some foam seat constructions a separate retainer or edge member is mounted to the pan adjacent the pan periphery and the element is used to compress the edge of the cover against the pan to shield the cover terminating edge from view and provide an attractive and utilitarian transition between the seat pan structure and the foam cushion. Devices of this type are shown in U.S. Pat. Nos. 3,823,980 and 4,018,479. However, as permanent fasteners are employed to attach the retainers to the pan the preliminary positioning of the retainer to the pan and to the cover is difficult to maintain and successful assembly is difficult to uniformly achieve under high production.
Previously, a practical and low cost method of assembly of a foam cushion having a vinyl cover to a substantially rigid pan wherein the necessary aesthetic prerequisites are met has not been available, and it is a basic object of the invention to provide such a foam rubber seat assembly.
It is an object of the invention to provide a seat having a foam cushion and a flexible vinyl cover supported upon a substantially rigid pan wherein tension forces within the cover constitute the sole means for positioning the seat cushion on the pan.
Another object of the invention is to provide a foam seat assembly utilizing a foam cushion having a flexible vinyl cover wherein the cushion is held upon a substantially rigid pan by tension forces within the cover which has been attached to a peripheral region of the pan.
An additional object of the invention is to provide a process for assembling a foam cushion having a vinyl cover to a substantially rigid pan wherein the cover is tensioned to pull the cushion toward the pan and while the cover is under tension it is preliminarily affixed to the pan prior to permanent attachment thereto.
Yet a further object of the invention is to provide a method for assembling a foam seat cushion to a substantially rigid pan wherein the cushion includes a cover having a flexible flap, the flap being tucked between the peripheral region of the pan and a retainer while under tension, the retainer including preliminary staking devices for maintaining the desired tension and positioning of the cover prior to the retainer being permanently affixed to the pan.
Another object of the invention is to provide a foam seat assembly using a foam cushion wherein the vinyl cover of the cushion includes a flap and a terminating edge and wherein the cover flap passing over the cushion periphery is tucked against the peripheral region of a substantially rigid pan receiving the cushion and a retainer overlapping the cover flap preliminarily stakes and finally compresses the cover flap between the retainer and pan, and also shields the cover terminating edge from view.
In the practice of the invention a foam cushion having an upper surface and a periphery includes a flexible vinyl cover bonded to the cushion upper surface and the cover includes a loose flap adjacent the cover periphery.
The cushion is supported on a relatively rigid pan having a peripheral configuration substantially corresponding to that of the cushion and the cushion rests upon the pan for support thereon. The cover peripheral flap is tucked, while under tension, between the pan peripheral region and a retainer which is to be mounted to the pan adjacent the pan periphery.
Preliminarily, the cover flap is tensioned and positioned and the retainer is positioned in a preliminary manner relative to the pan. The retainer includes elongated lances which pierce the tensioned cover flap holding the cover under tension as the retainer is finally positioned upon the pan. Fasteners such as screws or the like are used to firmly affix the retainer on the pan whereby the cover flap is sandwiched between the retainer and the pan and the retainer includes a bulbous edge providing an attractive and smooth transition between the pan associated structure and the cushion cover.
The initial tensioning and tucking of the cover flap relative to the pan, and the initial staking of the cover flap to the pan and retainer permits the process of the operation to proceed under high production techniques and the method of assembly of a seat in accord with the invention is economical and provides a durable and attractive seat assembly.